线性调频航管雷达风电场杂波背景下目标检测

Target Detection Under Wind Turbine Clutter Background for LFM Primary Surveillance Radar

传统动目标检测(Moving Target Detector, MTD)技术无法抑制具有频谱展宽特性的风电场杂波,可能导致目标检测概率下降和虚警率上升等问题。针对此问题,提出了一种线性调频航管雷达风电场杂波背景下的目标检测方法。该方法先进行风电场杂波抑制,再对杂波抑制后的数据基于MTD进行飞机目标检测。文中给出的风电场杂波抑制方法中,首先将传统谱中心补偿的风电场杂波抑制方法应用到线性调频体制雷达,针对此时存在的旁瓣抑制后的主瓣展宽问题,利用雷达参数信息优化恒虚警率(Constant False-Alarm Rate, CFAR)检测方法,再根据目标与杂波相对位置不同采用不同的方法抑制杂波。对于目标与杂波扩展主瓣在不同距离单元时,基于谱中心补偿及基于雷达参数的CFAR检测方法来检测并抑制风电场杂波;对于目标与杂波扩展主瓣在相同距离单元的情况,基于匹配追踪(Matching Pursuit,MP)算法抑制风电场杂波。仿真数据与实测数据实验结果表明该方法在保证有效检测目标的前提下能降低风电场杂波引起的虚警率。

The traditional Moving Target Detector(MTD)technology cannot suppress the clutter of wind farms with spectral broadening characteristics,which may cause the decrease of target detection probability and increase of false alarm rate.A target detection method against wind turbine clutter for linear-frequency modulation(LFM)Primary Surveillance Radar is proposed.The wind turbine clutter suppression is carried out before the traditional MTD target detection.In this paper,the traditional spectrum center compensation is applied to suppress clutter in the LFM radar system.As far as the problem of main lobe broadening,the parameters such as radar bandwidth and sampling rate are firstly used to optimize Constant False-Alarm Rate(CFAR)Detection.Different clutter suppression methods are then used according to the distance between target and clutter.For the case that target and the extended main lobe of clutter are in different range cells,the wind farm clutter suppressed based on the spectrum center compensation.Otherwise,matching Pursuit(MP)algorithm is used to mitigate wind turbine clutter.The performance of this algorithm was quantitatively analyzed.The experimental results show that the proposed method can reduce the false alarm rate caused by clutter on the premise of the effective target detection.